The present invention relates to DNA coding for uricase and a process for producing uricase. More specifically, the present invention relates to DNA coding for uricase, isolated from a microorganism belonging to the genus Cellulomonas, a recombinant plasmid containing said DNA, a transformant which carries said recombinant plasmid, and a process for producing uricase by culturing said transformant. The present invention further relates to a process for producing uricase by culturing a non-genetically engineered microorganism belonging to the genus Cellulomonas and being capable of producing uricase.
Uricase (EC 1.7.3.3) is an enzyme which catalyzes a reaction which oxidizes uric acid to produce allantoin, hydrogen peroxide and carbon dioxide, and is used for determining uric acid in the blood or urine, and usable as a component in a hair-dyeing kit, etc.
Heretofore, uricase has been produced by various microorganisms of the genera Candida (Japanese Published Examined Patent Application No. 5192/67), Micrococcus, Brevibacterium (Japanese Published Examined Patent Application No. 14783/69), Streptomyces (Agric. Biol. Chem. 33, 1282, 1969), Enterobacter (Japanese Published Examined Patent Application No. 19990/85; Agric. Biol. Chem., 44, 2811, 1980), and Bacillus (Japanese Published Unexamined Patent Application No. 280272/86, U.S. Pat. Nos. 4,882,280 and 4,987,076; Japanese Published Unexamined Patent Application No. 53488/90, GB 2221910A).
However, the known processes are still insufficient in efficiency of the production of uricase. There is a great demand for a process for producing uricase, in higher yield and at lower cost.
As the result of extensive studies in the process for producing uricase, it has now been found that a large amount of uricase can be produced by isolating DNA which codes for uricase from a microorganism belonging to the genus Cellulomonas, constructing a recombinant plasmid containing said DNA, transforming a suitable host strain with said recombinant plasmid, and culturing said transformant.